1. Field of the Invention
The invention relates to a device for measuring the reflection factor. The invention relates especially to a device for measuring the reflection factor for blood analyses and chemical analyses in which the concentrations of given components in samples are determined by the reflection factors of light with certain wavelengths.
2. Description of Related Art
Conventionally, a process in which the reflection factor at a certain wavelength is measured is known as a process for measuring the concentration of a component in a sample based on the color of a reaction substrate, for example, a reaction paper.
As FIG. 8 shows, Japanese Patent Application JP-A-2001-141644 discloses a device for measuring the reflection factor in which a reaction substrate is irradiated obliquely from overhead with light of a certain wavelength and in which the reflected light is determined directly above the reaction substrate. In this device for measuring the reflection factor, the use of a relatively large amount of the sample liquid (ml amount) is possible, and to a certain degree, the measurement is not adversely affected in the reaction substrate itself when the sample liquid volatilizes.
In the case of using blood or the like as the sample, a device is wanted in which a measurement is possible for an extremely small amount of sample (μl amount). However, in the device shown in FIG. 8 for measuring the reflection factor in the prior art, there is the disadvantage that at an extremely small amount of the sample volatilizes. Especially when using the above described sample, there are many cases of the use of enzyme reactions. In these cases, the sample itself is heated, by which more sample is vaporized.
To prevent vaporization, it can be envisioned that the reaction substrate might be coated with a transparent component. In the above described process in which the reflection light is received by the conventional oblique light irradiation directly above the reaction substrate, there are, however, the disadvantages that the light which has been reflected by the transparent substrate leads to faulty radiation which is captured by the detector and that the sensitivity of determination decreases.